Method of spreading the ends of rectangular metal bars



(No Model.)

W. R. WEBSTER.

METHOD OF SPREADING THE ENDS 0P RECTANGULAR METAL BARS.

No. 380,414. Patented Apr. 3, 1888.

Z A l V WETNEZSSES:

Usirrzen drains l ATENr @rrrca 'WILLIAM It. WEBSTER, OF PHILADELPHIA, PENNSYLVANIA.

METHOD OF SPREADING THE ENDS 0F RECTANGULAR METAL BARS.

SPECIFICATION forming part of Letters Patent No. 380,414, dated April 3. 1983- Application filed August 20, 1887. Serial No. 247,415. (No model.)

To aZZ whom it may concern:

Be it known that I, \VILLIAM R. Wnnsrnn, of the city and county of Philadelphia, State ofPcnnsylvania, have invented a new and useful Improvement in the Method of Spreading the Ends of Rectangular Metal Bars to Form Eye-Bars, of which the following is a true and exact description, reference being had to the accompanying drawings, which form apart of this specification.

My invention relates to the spreading and thickening of the ends of rectangular metal bars in the process of converting them into what are known as eye-bars for bridges and the like.

Prior to my invention eye-bars were formed from fiat rectangular bars by methods which, while differing in some details, may be grouped as follows: First, by upsetting the heated end of a bar in a die of the required shape and while it was clamped between plain die-faces; second, by piling the end to be formed into an eye and then swaging the thickened end into shape; third, by upsetting the end of the bar in dies in which the sides, faces, or both the sides and faces, were made to yield or move outward, so as to permit the bar to spread or spread and thicken without at any time leaving room enough for any considerable bending or buckling; fourth, by upsetting the end so as to thicken it, then upsetting the thickened end in spreading dies, and then forging down the spread and thickened end to the required shape and thickness in forming dies. The necessity of the two upsetting operations in the lastinentioned method arose from the difiiculty found in preventing the bars from folding and buckling, the only method practiced for preventing this being to so form the dies that they would engage the corners or edges of the bars, and thus support them longitudinally while being upset, a plan sufficiently effective when thickening the ends, but not practicable where any considerable spreading was required. The spreading of the eye in this method was accomplished by the same means as in the first; but the preliminary thickening diminished the tendency to buckle or fold between the flat die-faces. Another method practiced was by forming an enlarged end on the bar in rollingit,and spreading this end out by a hammer.

Now,1 have discovered that by clamping the end of a bar heated to the temperature necessary for upsetting between die-faces, in one or both of which a longitudinal groove or depression is formed so as to lie under or over the medial line of the flat sides of the bar throughout the length of its heated end, and then upsetting the bar by pressure upon its end acting in the line of the central groove or depression, the said bar will be entirely free from any tendency to buckle or bend sidewise and will be expanded or spread evenly on both sides of its center line, the reason for this be' ing that a longitudinal head or projection is formed all along the center of the flat side or sides of the heated bar end corresponding with and filling the longitudinal groove or grooves in the die-faces, and the end of the bar is thus, as it were, interlocked with the die-face, and all tendency to bend is overcome, while the freedom of the bar to spread on each side of the center line is in nowise interfered with.

It is not at all necessary that the bar should be tightly clamped between the upper and lower die-faces of the spreading die, as the first action of the upsetting-plunger will cause the soft metal of the heated end to expand into the groove of the die-face, and the continuation of the pressure only serves to increase and maintain the hold of the bead thus formed on the bar upon the grooved dieface.

I have in another application described the use of a spreading die made up of one dieface having the central longitudinal groove and another die-face having a corresponding projection, which said projection coacted with the groove in preventing buckling in the bar, and of course a plan flat-faced die might be used in connection with the grooved die. The conjoint use of a grooved lower die with a similarly-grooved upper die has, however, the advantage of producing an eye which, on leaving the die, is thickest along its center line, and which, therefore, has a surplus of metal at its end. As a result of this the subsequent work put upon the eye in completing it serves to consolidate and strengthen the end of the bar which has to bear the strain of the pin.

Reference being now had to the drawings, which illustrate dies adapted for use in my new process, Figure 1 is an end elevation of such a die; Fig. 2, a plan view of the lower die-face. Fig. 3 is an end elevation of the die, showing the bar to be spread therein with the projecting bead formed thereon; and Fig. 4 shows in perspective a bar having along the center of each of its flat sides the longitudinal beads or projections by which it interlocks with the grooved die-faces.

A and B are the upper and lower die'faces, constituting together,and with the usual cheekpieces, plunger, 800., the spread die.

C is a flat rectangular bar of the kind for which my improved process is adapted.

1 and 2 represent the spaces into which the metal of the bar is forced in the process of spreading.

1) indicates the central longitudinal groove formed in the die-faces, and 0 indicates the bead or projection by which the flat rectangular bar is interlocked with the die-face.

, From. what has been already said the mode of handling the bar in carrying out my process will be readily understood. The end to be spread into an eyeis first heated to the required temperature and then placed in the die, so that the center of one of its flat sides will lie throughout along the longitudinal groove formed in the die-face which supports its said side. The bar is then clamped in the usual way to resist a longitudinal thrust, and the upper die, which is also preferably grooved, but may be of any desired form, is placed in position upon the opposite side of the flat bar and firmly secured in place. The plunger then acts against the heated end of the bar, its line of motion being parallel to the groove or grooves formed in the die-faces, and the metal of the bar is upset and forced backward into the dies. Thepressure being equal in all directions, the metal will flow not only into the cavities 1 and 2, butalso into the grooves b, which will soon be completely filled by the metal andkept full during the whole of the upsetting action.

In cases where it is desirable that'the eye formed in the spreading die should have a considerable excess of metal at the center, this is easily accomplished by increasing the breadth and depth of the longitudinal grooves 1n the die-faces, and a Very considerable thickening of the bar in the most desirable place can thus be brought about.

It is of prime importance that the groove or grooves '1) should extend over the wholelength of the heated bar end, so as to engage it from end to end and prevent the least tendency to bend during upsetting, for if the free end of the bar is bent at any point it is impossible to afterward correct the distortion, and the metal in the eye will be unevenly distributed even if the distortion is not sufiticient to make what is known as a buckle or fold.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is-

The process of spreading the end of a rectangular metal bar, which consists in heating said end to the required temperature for upsetting, clamping it between die-faces, one or both of which are provided with a continuous central longitudinal depression or groove arranged to lie along the whole length of the heated end, and then upsetting it by pressure on its end and in the line of the centralgroove in the supporting die-face, all substantially as specified, and so that the heated end of the bar will be distorted and engaged with the grooved die-face along its medial line and throughout its length during the upsetting.

' WM. R. WEBSTER. Witnesses:

CHAS. A. BUTTER,

CHAS. A. MAHONY. 

